1. Field of the Invention
The present invention relates to a vehicle arranged for movement along a track, and also to a tracked vehicle system for such a vehicle.
2. Summary of the Prior Art
There is increasing interest in the design of a vehicle which is to be driven along the track making use of electromagnetic drive forces to lift and/or propel the vehicle along the track. Such vehicles are known as Maglev vehicles, and have the advantage that such vehicles are capable of reaching much higher speeds than ordinary track vehicles (e.g. about 500 km/hr) because there is no direct vehicle/track contact. Of course, for slow speeds, such a vehicle will have wheels which run on the track, but if the vehicle increases in speed, the magnetic effects predominate.
The development of Maglev vehicles has been linked to the development of superconducting magnets, because a Maglev vehicle needs to have at least one (usually many) superconducting magnets which interact with coils in the track to support and propel the vehicle. In general, the track will have normal conducting coils which, together with the superconducting magnet(s), generate a lifting force for supporting the vehicle clear of the track, and other coils which, again together with the superconducting coils, generate a propulsive force.
There have been a number of proposals for making use of aerodynamic effects on a Maglev vehicle. For example, in the article entitled "Development of Aerodynamic Brake of Maglev Vehicle for Emergency Use" by Koda et al. in International Conference Maglev '89 (July 1989), pages 281 to 286, there was proposed an aerodynamic brake for such a vehicle. The aerodynamic brake comprised one or more plates which were movable so as to move between a position in which they were generally flush with the body of the vehicle to a position in which they extended outwardly from it so as to increase the drag of the vehicle and therefore slow it down.
In JP-A-48-9416 there was proposed an arrangement in which flat fins extended along the length of the Maglev vehicle, the drag of those fins resisting pitching of the vehicle. Furthermore, in JP-A-48-9417 it was proposed that the Maglev vehicle had flat stabilizers which could be moved out from a position flush with the body of vehicle to a projecting position, in which projecting position they applied a lift to the part of the body to which they were attached, due to their angle of incidence with the direction of movement.